|How the diaphragm works.|
Now, what happens when we fail to use, or hardly use, our diaphragm when breathing? Terrible things! Most people are 'chest breathers'. Chest breathers are shallow breathers. They use only the top portion of their lungs. They don't fill up the bottom part. Chest breathing is a very 'shallow' and ordinarily haphazard and non-rhythmic form of breathing, with almost all the outward movement being confined to the upper chest. One of the results of chest breathing is that the lungs are never filled completely, so the body rarely, if ever, receives sufficient oxygen. That is not good. There is a lung condition known as atelectasis, which is the collapse or closure of a lung resulting in reduced or absent gas exchange. It may affect part or all of a lung. There are several causes of atelectasis, but one of them is—you guessed it—shallow chest breathing. What we don’t use, we lose. If we don’t use all of our lungs, we end up with part of our lung collapsing or closing. Not nice at all. When we breathe correctly—that is, breathing deeply using our diaphragm—we use the bottom of our lungs as well as the top.
Atelectasis of the right lower lobe seen on chest X-ray.
(Source: Hellerhoff. Wikipedia.)
Mouth breathers are invariably chest breathers, but chest breathers aren't confined to mouth breathers. When we breathe with our chest, the neck, shoulders and upper rib muscles are all 'engaged' as our chest 'elevates' toward our chin when breathing inwards. The result? Chronic neck and shoulder tension which, of course, lead to pain. Worse, over time there can be noticeable postural changes in the body such as a forward shift in the head and a rounding of the shoulders. When the head is pulled forward, the additional pressure on the neck, shoulders and back rises dramatically. The result? Well, there are several, but one of the nastiest is tissue damage ... and more pain. Every 2.5 cm (inch) that the head is thrust forward from its natural position adds another 4.5 kg (10 lbs) of stress and pressure on the neck, shoulders, back and spine. More bad stuff.